Valve reseating tool



March 29, 1955 H. w. NYLUND 2,704,911

VALVE RESEZATING TOOL Filed NOV. 18, 1952 INVENTOR Harry W. Nylund,

m/zdaae. ATTO'RN EYs.

United States Patent O VALVE RESEATING TOOL Harry W. Nylund, Bridgetown, Barbados, British West Indies Application November 18, 1952, Serial No. 321,089

1 Claim. (CI. 5126) This invention relates to valve reseating tools and more particularly to a tool for reseating a valve seat spider in an oil well pump.

It is among the objects of the invention to provide an improved hand tool for lapping in the removable seats of pump valves, particularly the valves used on mud and 011 pumps for oil wells; which can be attached to a movable seat and the seat placed in a valve chamber and turned to grind or lap the seat between the removable valve seat and wall of the valve chamber; which includes spring means for regulating the pressure applied to the removable valve seat during the lapping operation and a universal oint which permits the removable valve seat to properly align itself in the valve chamber; and which is simple and durable in construction, economical to manufacture, and easy to use.

Other objects and advantages will become apparent from a consideration of the following description and the appended claim in conjunction with the accompanying drawing wherein:

Figure l is a cross sectional view through a valve chamber structure of an oil well pump valve and through a removable valve seat mounted in the valve chamber showing in side elevation a valve lapping hand tool illustrative of the invention connected to the removable valve seat;

Figure 2 is a cross sectional view of the valve lapping tool on the line 22 of Figure 1;

Figure 3 is a perspective view of the lower end portion of the tool as illustrated in Figure 1;

Figure 4 is a fragmentary cross sectional view on the line 44 of Figure l; and

Figure 5 is a cross sectional view on the line 5-5 of Figure 1.

With continued reference to the drawing, the portion of the pump valve illustrated comprises a cast iron valve structure enclosing a valve chamber 11 and including a partly cylindrical wall 12 surrounding the valve chamber and open at its upper end and a partition wall 13 spaced from the lower portion of the outer wall of the valve chamber and providing a fiuid passage 14. The partition wall 13 terminates at the adjoining ends of the valve chamber 11 and fluid passage 14, and a circular seat 15 extends around the inner edge of the partition wall 13 and around a portion of the outer wall 12 of the valve structure at the bottom end of the valve chamber 11. The valve structure also provides fiuid outlet passages 16 and 17 leading from the chamber 11.

A removable valve seat member, generally indicated at 18, is mounted in the seat 15 and includes a circular rim 19 having a peripheral surface which closely fits the surface of the seat 15 and is provided on its upper side and inwardly of its peripheral surface with a beveled valve seat 20 for a pressure operated valve head. The removable valve seat 18 also includes a hub 21 having a tapered aperture 22 extending therethrough coaxially of the peripheral surface of the circular rim 19 and angularly spaced apart spokes 23 extending between the hub and the inner side of the rim 19 and supporting the hub in the A valve stem bushing 24 is mounted in the aperture 22 and has at one end an external, annular flange overlying the upper end of the hub 21.

The peripheral surface of the removable valve seat 18 and the complementary surface of the seat 15 provided in the valve chamber housing are subject to wear by sand and other abrasives forced with liquid by the pump past the valve and when this wear has progressed to a suflicrent ice extent, it becomes necessary to remove and reseat the movable valve seat 18.

After the movable valve seat has been removed from the valve chamber, metal is added to its peripheral surface by a welding operation to replace the metal worn away from the peripheral surface of the valve seat 18 and the surface of the seat 15 in the valve chamber, and the peripheral surface of the movable valve seat is then ground down until it is slightly oversize relative to the annular seat 15 in the valve chamber housing.

The present invention provides a hand tool for conveniently lapping the repaired movable valve seat 18 into the annular seat 15 in the valve chamber housing, it being noted that the peripheral surface of the movable valve seat 18 and of the housing seat 15 are tapered in a direction away from the valve chamber 11 so that the movable valve seat will move through the annular seat 15 to a limited extent only.

The valve reseating tool of the present invention comprises an elongated stem 25 including two parts 26 and 27 connected together in end to end relationship by a universal joint connection 28. The stem portion 26 is longer than the portion 27 and may be conveniently provided by a length of cylindrical metal tubing of a suitable diameter. The shorter stem portion 27 is preferably solid and of cylindrical shape and has at its end remote from the portion 26 a coaxially disposed end portion 29 of reduced diameter provided at its distal end with external screw threads 30. A driving plate 31 is provided with a centrally disposed aperture receiving the reduced end portion 29 of the stem portion 27 and is secured to this stem portion at the proximal end of the reduced end portion 29. The opposite ends of the plate 31 are inclined outwardly and toward the distal end of the reduced end portion 29 and are slotted to provide at each end of the plate 31 a pair of spaced apart fingers, as indicated at 32.

The reduced end portion 29 of the stem portion 27 has a diameter substantially equal to the internal diameter of the bushing 24 and a length somewhat greater than the length of this bushing. When the movable valve seat 18 is secured to the tool the reduced end portion 29 is inserted through the bore of the bearing bushing 24 and the pair of fingers 32 at each end of the plate 31 are disposed at respectively opposite sides of corresponding spokes 23 of the valve seat 18, as illustrated in Figure 5. A nut 33 1s then threaded onto the screw threaded distal end portlon of the stem portion 27 to firmly secure the stem to the movable valve seat 18, the valve seat being constrained ttll it otgaie with the tool stem by the fingers of the driving p a e A positioning or mounting plate 35 of elongated, rectangular shape is provided with a central aperture receivmg the part 26 of the stem 25 and ball bearings 36 and 37 are mounted on the plate 35 surrounding the stem receiving aperture 38 in this plate and receiving the stem part 26 to ournal the stem in the positioning plate. The bearmg 36 1s a radial ball bearing, and the bearing 37 is an axlal or thrust ball bearing and both bearings are secured to the plate 35 by an annular housing 39 which receives the bearings and is secured to the plate.

The positioning plate 35 has a length such that it spans the open upper end of the valve chamber housing 10 and is provided with notches, one at each corner thereof, as indicated at 40, which receive stud bolts 41 projecting upwardly from the open end of the valve chamber housing to secure a cover plate, not illustrated, over the open end of the housing.

Curved bails 42 and 43 are mounted on and extend upwardly from the plate 35 at respectively opposite sides of the bearing housing 39 and serve as handles for conveniently carrying the tool.

A turning handle 45 is mounted on the stem at the end of the stern part 26 remote from the part 27, and a collar 46 receives the stem between the positioning plate 35 and the turning handle 45. This collar 46 is movable along the stem and is secured in selected positions of adjustment longitudinally of the stem by suitable means, such as the thumbscrew 47 which extends through a radially disposed tapped hole in the collar 46 and engages the stem portion 26 at its inner end.

A coiled compression spring 48 surrounds the stem part 26 between the collar 46 and the thrust bearing 37 and has its lower end bearing on the upper surface of the thrust bearing 37 and its upper end bearing against the lower surface of the collar 46, this spring being effective to resist downward pressure manually applied to the stem 25 through the turning handle 45 and the collar 46 being adjustable along the stem to vary the pressure resisting effect of the spring 48.

A collar 50 receives the stem portion 26 between the positioning plate 35 and the universal joint connection 28 and, when brought into contact with the adjacent side of the positioning plate, provides a limit stop for movement of the stem through the positioning plate by the compression spring 48. e

In reseating the repaired removable valve seat 18, this valve seat is secured to the part 27 of the valve stem in the manner indicated above, and positioned in the housing seat 15. The positioning plate 35 is then positioned on the open end of the valve chamber housing with its opposite ends between adjacent stud bolts 41 and, with suitable grinding compound applied to the peripheral surface of the movable seat 18, rotational movements are imparted to the turning handle 45 of the tool and through the tool to the movable valve seat 18 until the peripheral surface of this valve seat is lapped into the housing seat 15 to the desired extent.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is, therefore, to be considered in all respects as illustrative and not restric tive, the scope of the invention being indicated by the appended claim rather than by the foregoing description,

and all changes which come within the meaning and range of equivalency of the claim are, therefore, intended to be embraced therein.

What is claimed is:

In a tool for lapping a valve seat into an opening in a valve structure, a mounting plate adapted to be fixedly mounted on the valve structure in line with the valve seat opening, means for securing the mounting plate directly to the valve structure, said mounting plate being provided with an opening, a bearing fixed on the mounting plate and surrounding said mounting plate opening, a stem extending through said opening and rotatably and slidably engaged with and supported by said bearing, said stem having an outer end portion and an inner end portion extending at opposite sides of said mounting plate, a helical spring circumposed on said outer end portion and compressed between said bearing and a part of said outer end portion, said inner end portion of the stem having a terminal end, a valve seat driving plate, flexible means operatively connecting said driving plate non-rotatably to said terminal end, and means on said outer end portion of the stem for rotating the stern and for moving said stem inwardly against the resistance of said spring.

References Cited in the file of this patent UNITED STATES PATENTS 527,748 Hill Oct. 16, 1894 1,009,243 Hart Nov. 21, 1911 1,384,625 Moore July 12, 1921 2,431,777 Smith Dec. 2, 1947 

